Production of Charm-Meson Molecules in Thermal Environments

The evidence of production of $X(3872)$ in heavy-ion collisions provides a new opportunity to discriminate between its nature as a loosely bound molecule or compact tetraquark.

Loosely bound molecules are governed by universal physics; one of the universal properties of these remarkable systems is the Tan contact which determines the density of loosely bound states in a system, and is widely used to study strongly interacting Fermi gases of ultracold atoms.

Here, we study the production of loosely bound charm-meson molecules in sufficiently dilute thermal environments, such as those produced by heavy-ion collision, by employing the Tan relations for the contact.